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100 _aForke, Sven
_951397
245 _aSources of laminated sediments in the northeastern Arabian Sea off Pakistan and implications for sediment transport mechanisms during the late Holocene/
260 _bSage,
_c2019.
300 _aVol 29, issue 1, 2019 : (130-144 p.).
520 _aLaminated sediments of the continental slope off the Makran coast in the northern Arabian Sea are well-known climate archives and record productivity, as well as supply of material from land. Here, we studied sediment core 275KL off Pakistan in concert with sediment trap, dust and river samples in order to characterize and quantify land-derived material deposited in varves and event layers. We analysed grain sizes, mineral assemblages, bulk components and stable isotopes (δ13C, δ18O) of carbonates. In winter, enhanced river discharge is the main source of lithogenic matter contributing the major amounts to the total annual sedimentation of the northern Arabian Sea. During the late summer season, lithogenic matter accumulation is slightly enhanced, probably carried along with the south-eastward blowing Levar winds from the Balochistan and the Sistan Basins and the summer monsoon discharge maximum of perennial streams. C/N ratios and stable carbon and oxygen isotopes could not be used to distinguish between organic matter produced on land and in the ocean, whereas stable carbon and oxygen isotope ratios of carbonates suggest that sedimentation of event layers is dominated by direct inputs from land. Catastrophic denudation and storm events occur on average once every 50 years and lead to sedimentation rates that exceed the mean annual sedimentations of 983 g m−2 yr−1 by 6 to 10 times. Nevertheless, due to their rare occurrence, they contributed only 7% to the total sedimentation during the last ca. 5000 years. End-member modelling of grain sizes in accordance with lithogenic matter accumulation rates and event layer frequencies showed that arid conditions prevailed between 4000 and 5000 a BP while more humid conditions commenced around 2000 ka BP in accordance with the Pacific ENSO record.
650 _a Arabian Sea,
_951398
650 _aENSO,
_951399
650 _a erosion,
_950967
650 _a grain size,
_951400
650 _a Holocene climate,
_951401
650 _a laminated sediments,
_951402
650 _a lithogenic matter,
_951403
650 _awestern disturbances
_951404
700 _aRixen, Tim
_951405
700 _aBurdanowitz, Nicole
_951406
700 _aLückge, Andreas
_951407
700 _aRamaswamy, Venkitasubramani
_951408
700 _aMunz, Philipp
_951409
700 _aWilhelms-Dick, Dorothee
_951410
700 _aVogt, Christoph
_951411
700 _aKasten Sabine
_951412
700 _aGaye, Birgit
_951413
773 0 _012756
_916504
_dLondon: Sage Publication Ltd, 2019.
_tHolocene/
_x09596836
856 _uhttps://doi.org/10.1177/0959683618804627
942 _2ddc
_cART
999 _c12767
_d12767